Incorrect Plumbing for SWG - How worried should I be


Jun 20, 2007
New to TFP. What a great site. I have a new pool and and Jandy Aqua Pure SWG. The Pool builder has plumbed the Flow Sensor between the pump and the filter rather than right before the SWG. Everythings ok unless I vac to waste when the cell thinks it has flow but doesn't. Aqua Pure manual says danger of explosion if cell is on without flow. Is this lawyer talk or is there a real danger? Right now I'm setting SWGoutput to 0% before I vac to waste as a temporary workaround.

Any insights would be greatly appreciated.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
Welcome to TFP!

There is a real danger. If the cell is on without flow, hydrogen gas will accumulate at the highest point above the cell. At some point that could cause an explosion. Normally the water flow pushes the gas into the pool where it harmlessly bubbles out. The bubbles are generally so small you can hardly see them. I imagine that you will eventually forget to turn the unit off when vacuming and be at risk, or someone else will come along and not know to turn the cell off and you could be liable.

The builder has to fix this.


Jun 20, 2007
Lion, Sean, Thanks for the quick reply. It's on my punch list, and based upon your response, I'll elevate the priority.

Thanks again.


What is with some pool builders? Mine did the same thing and I pointed out his error (along with several others that he made in automation system). When he realized that I knew a few things about pools he fixed them all without any complaints! ;)


TFP Guide
In The Industry
May 14, 2007
New Brunswick Canada
Aww cmon guys, we all know tis the first thing these boys throw out...THE INSTRUCTIONS

That is horrible that they did that, can only imagine what could of happened if an explosion occured.



TFP Expert
LifeTime Supporter
Mar 29, 2007
Coastalish 'down easter'
Hey guys!
Not all PBs are incompetent!, just the majority - it helps keep me in business :wink: Rik, I have all the installation/ user manuals for the equipment we install. I'm not gonna try to make excuses for other PBs, but the company I work for trys as hard as is humanly possible to not have to go back for warantee work (my boss gives a 5 yr warantee on everything we do)... sometimes, things will go wrong - we correct it, often before the pool owner realizes something's not right. Just wanted everyone to know that not every pool company is staffed by 'hacks' :cheers: